Minimal HTTP client based on netcat

microhttp

#!/bin/sh
#
# Send HTTP request with minimal dependencies, suitable to run on BusyBox.
# Requirements: "sed" and "nc" (netcat).
#
# Synopsis::
#
#   microhttp POST http://john:acme@httpbin.org/post "foo=bar&baz=qux"
#

parse_url() {
    # https://stackoverflow.com/questions/6174220/parse-url-in-shell-script/37750441#37750441
    eval $(echo "$1" | sed -e "s#^\(\(.*\)://\)\?\(\([^:@]*\)\(:\(.*\)\)\?@\)\?\([^/?]*\)\(\(.*\)\)\?#${PREFIX:-URL_}SCHEME='\2' ${PREFIX:-URL_}USER='\4' ${PREFIX:-URL_}PASSWORD='\6' ${PREFIX:-URL_}HOST='\7' ${PREFIX:-URL_}PATH='\9'#")
}

send_request() {

    HTTP_METHOD=$1
    HTTP_URI=$2
    HTTP_BODY=$3

    PREFIX="URL_" parse_url "${HTTP_URI}"

    # Compute authentication header.
    [[ ! -z ${URL_USER} ]] && auth_header=$(token=$(printf "${URL_USER}:${URL_PASSWORD}" | base64); printf "Authorization: Basic $token"; printf '\\r\\n')
    [[ ! -z ${HTTP_BODY} ]] && post_header="Content-Type: application/x-www-form-urlencoded\r\nContent-Length: $(printf "${HTTP_BODY}" | wc -c)\r\n"

    # Build request.
    request="${HTTP_METHOD} ${URL_PATH} HTTP/1.1\r\nHost: ${URL_HOST}\r\n${auth_header}${post_header}\r\n${HTTP_BODY}"

    # Prepare "netcat" command.
    # https://egeek.me/2014/08/17/sending-http-post-request-with-netcat/
    command="nc ${URL_HOST} 80"
    [[ $HTTP_METHOD = "POST" ]] && command="nc -w 1 -i 1 ${URL_HOST} 80"

    # Debugging.
    echo "Command: ${command}"
    echo
    echo ${request}

    # Send request.
    printf "${request}" | ${command}

}

send_request "$@"

Thanks.